Charles Dickens died before he could finish his extraordinary murder novel, and that is only the beginning of the mystery. Both sinister and hilarious, this play picks up where Dickens left off.

“The Mystery of Edwin Drood” is a comical play-within-a-play, featuring actors at London’s Music Hall Royale in the late 1800s. Each character is an actor who plays a particular role in a show at the music hall.

Throughout the production, the Chairman, a master of ceremonies of sorts, speaks to the audience and explains their responsibility in determining the end of the show. In the second act, Edwin Drood has disappeared, and there are eight suspects who may have contributed to his assumed demise. Along with the murder mystery, there are several intertwined love stories, and the audience also must vote to decide which characters will end up together.

“The possibilities are almost endless when you consider the different pairings of romantic interests, along with the selection of the murderer,” said Wil Kilroy, director of the production and USM professor of theatre.

“Another aspect that will change for each performance is the title role, which is double-cast,” Kilroy said. Eileen Hanley and Emily Davis, each USM senior musical theatre majors, will alternate playing Edwin Drood for each performance.

Along with a distinctive ending for each show, there also will be a unique beginning — and it starts as soon as audiences enter Russell Hall. The Chairman and Victorian-era costumed characters will be roaming through the crowd and greeting guests as they arrive. The audience interaction doesn’t stop there.

“The Mystery of Edwin Drood” was inspired by British pantomime and music hall traditions, in which actors continually interact with the audience and welcome participation, such as hissing at the villain.

“Audience interaction is rampant throughout the show,” said Edward Reichert, the show’s musical director and USM lecturer. “There is one number in particular that really heats things up. Princess Puffer’s rendition of ‘The Wages of Sin’ is not for the faint of heart. Married couples sitting down front: beware!”

Other well known songs include “Moonfall” and “The Writing on the Wall.” Rupert Holmes wrote the book, music and lyrics for “The Mystery of Edwin Drood,” which debuted on Broadway in 1985 and won five Tony Awards including best musical, best book of a musical and best original score.

Reichert noted that the show’s music “perfectly exemplifies the show’s sassy and saucy flavor.” There will be a five-piece band comprised of USM students majoring in music, and Kellie Moody, USM senior piano performance major, will provide accompaniment and is the associate musical director.

Vanessa Beyland, choreographer for the production, worked with Kilroy, Reichert and the cast to extend the British music hall tradition into song and dance numbers, including “There You Are,” “Don’t Quit While You’re Ahead,” “Off to the Races” and “Both Sides of the Coin.”

“Because the show is a musical within a musical, the dances help bring the audience into the world of the performer and the story being presented,” Beyland said. “There is a lot of playing to the audience, gimmicks and larger-than-life moves and gestures.

“Rehearsals have been a blast,” the choreographer added. “Everyone comes with such energy and enthusiasm, it has inspired me to create very fun and entertaining choreography.”

While characters continually interact with the audience during the show, there may be a few lucky audience members who will actually be seated within the Music Hall Royale.

“We are not only creating scenic elements that are specific to the play, but we are also creating the fictitious 19th-century Music Hall Royale, where our production is being performed,” said Charles Kading, set designer for the production and USM professor of theatre. “We hope to seat a pair of audience members each night in the Music Hall Royale box seats onstage, flanking the performance area.”

Tickets are $21, general public; $15, seniors, USM employees and alumni; $11 students. A special reduced-price matinee at 5 p.m., Wednesday, March 19 offers all tickets at just $10. For more information, call 207-780-5151 or go to www.usm.maine.edu/theatre.